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In this paper, we present two methods for registering desired defect lattices within background periodic lattices through spatial light-modulator-based holographic lithography. In the first method, the diffraction efficiency from the engineered phase pattern was used to locally modify the fill fraction of polymerized materials in holographic structures, and, at the same time, we achieved the lattice matching between modified and background regions. In the second method, we registered spatially variant lattices for a 90 deg bend within the background periodic lattices through two steps of phase engineering of the laser beam.Stable optical trapping of dielectric nanoparticles with low power high-repetition-rate ultrafast pulsed excitation has received considerable attention in recent years. However, the exact role of such excitation has been quite illusive so far since, for dielectric micron-sized particles, the trapping efficiency turns out to be similar to that of continuous-wave excitation and independent of pulse chirping. In order to provide a coherent explanation of this apparently puzzling phenomenon, we justify the superior role of high-repetition-rate pulsed excitation in dielectric nanoparticle trapping which is otherwise not possible with continuous-wave excitation at a similar average power level. We quantitatively estimate the optimal combination of pulse peak power and pulse repetition rate leading to a stable trap and discuss the role of inertial response on the dependence of trapping efficiency on pulse width. In addition, we report gradual trapping of individual quantum dots detected by a stepwise rise in a two-photon fluorescence signal from the trapped quantum dots which conclusively proves individual particle trapping.The Gerchberg-Saxton (GS) algorithm is widely used to calculate the phase-only computer-generated hologram (CGH) for holographic three-dimensional (3D) display. However, speckle noise exists in the reconstruction of the CGH due to the uncontrolled phase distribution. In this paper, we propose a method to suppress the speckle noise by simultaneously reconstructing the desired amplitude and phase distribution. The phase-only CGH is calculated by using a double-constraint GS algorithm, in which both the desired amplitude and phase information are constrained in the image plane in each iteration. The calculated phase-only CGH can reconstruct the 3D object on multiple planes with a desired amplitude distribution and uniform phase distribution. Thus the speckle noise caused by the phase fluctuation between adjacent pixels is suppressed. Both simulations and experiments are presented to demonstrate the effective speckle noise suppression by our algorithm.The responses of fused taper couplers with different structure parameters to ultrasonic waves have been investigated theoretically and experimentally. A comprehensive analysis of the acousto-optic interaction was presented, taking into account the elasto-optic geometric effect. It is found that direct deformation of the coupler induced by ultrasonic waves is the critical factor in the sensing mechanism and is closely related to the sensor sensitivity. Moreover, the strain response of the coupler with different structure parameters was analyzed using a 3D coupled acoustic-solid numerical model, which was based on the developed mathematical model. According to the theoretical analyses, related experiments were carried out, and experimental results show that this ultrasonic sensor with a longer stretching length has higher sensitivity and the sensitivity of the sensor takes a nonmonotonic relation with an aspect ratio, which are consistent with the theoretical analyses results. We argue that our work may provide a useful guide in designing and optimizing more sensitive ultrasonic sensors used in practical ultrasonic detection.Surface roughness is an important factor in characterizing the performance of high-precision optical surfaces. In this paper, we propose a model to estimate the surface roughness generated by a single-point diamond turning machine. In this model, we take into consideration the basic tool-cutting parameters as well as the relative vibration between the tool and the workpiece in both the infeed and feeding directions. Current models focus on the relative tool-workpiece vibration in the infeed direction. However, based on our experimental measurements, the contribution of relative tool-workpiece vibration in the feeding direction is significant and cannot be ignored in the model. www.selleckchem.com/JAK.html The proposed model is able to describe the surface topography for flat as well as cylindrical surfaces of the workpiece. It has the potential to describe more complex spherical surfaces or freeform surfaces. Our experimental study with metal materials shows good correlation between the model and the diamond-turned surfaces.Catadioptric omnidirectional images exhibit serious nonlinear distortion due to the involved quadratic mirror. Conventional pinhole model-based methods perform poorly when directly applied to the deformed omnidirectional images. This study constructs a catadioptric geometry system to analyze the variation of the neighborhood of an object in terms of the elevation and azimuth directions in a spherical coordinate system. To accurately represent the distorted visual information, a parametric neighborhood mapping model is proposed based on the catadioptric geometry. Unlike the conventional catadioptric models, the prior information of the system is effectively integrated into the neighborhood formulation framework. Then the distortion-adaptive neighborhood can be directly calculated based on its measurable image radial distance. This method can significantly improve the computational efficiency of algorithm since statistical neighborhood sampling is not used. On the basis of the proposed neighborhood model, a distortion-invariant Haar wavelet transform is presented to perform the robust human detection and tracking in catadioptric omnidirectional vision. The experimental results verify the effectiveness of the proposed neighborhood mapping model and prove that the distorted neighborhood in the omnidirectional image follows a nonlinear pattern.A symmetric hybrid plasmonic waveguide (SHPW) configuration based on quasi-phase-matched (QPM) four-wave mixing (FWM) is proposed to realize efficient FWM conversion between the C-band and mid-infrared (mid-IR) regions. Due to the ability to allow strong confinement of light, an extremely large nonlinear parameter γ>10) are achieved by optimally designing the SHPW geometrical parameters. In addition, a QPM technique is adopted to achieve a relatively long effective length of FWM nonlinear process by constructing a long SHPW grating, thereby resulting in highly efficient wavelength conversion without rigorous dispersion engineering of waveguide structures. By using numerical simulations we have demonstrated that, for a pump wavelength of 1,800 nm, an efficient and flat FWM conversion of ∼-17  dB (∼-22  dB) could be realized around a target signal wavelength of the C-band 1,530-1,565 nm (mid-IR 2,118-2,180 nm), in a 1,000 μm-long grating with a serious phase mismatch.Access to hydroxy-functionalized P-chiral phosphine-boranes has become an important field in the synthesis of P-stereogenic compounds used as ligands in asymmetric catalysis. A family of optically pure α and β-hydroxyalkyl tertiary phosphine-boranes has been prepared by using a three-step procedure from readily accessible enantiopure adamantylphosphinate, obtained by semi-preparative HPLC on multigram scale. Firstly, a two-step one-pot transformation affords the enantiopure hydroxyalkyl tertiary phosphine oxides in good yields and enantioselectivities. The third step, BH3 -mediated reduction, allows the formation of the desired phosphine-boranes with excellent stereospecifity. The mechanistic study of this reduction provides new evidence to elucidate the crucial role of the pendant hydroxy group and the subsequent activation of the P=O bond by the boron atom.

von Willebrand factor (VWF) plays a critical role in platelet adhesion and aggregation after vascular injury and at sites of high shear rate. Elevated VWF levels are associated with an increased risk of ischemic cardiovascular events; however, it is unclear whether VWF deficiency is protective against atherosclerosis. We aimed to compare the prevalence of cardiovascular disease (CVD) among patients with and without von Willebrand disease (VWD).

A cross-sectional analysis was performed on discharge data for adults from the Nationwide Inpatient Sample (NIS) between the years 2009 and 2011. CVD was defined as ischemic heart disease, myocardial infarction, ischemic cerebrovascular disease, or peripheral vascular disease. For prevalence calculations and statistical analyses, we used discharge-level weights provided by the NIS to reflect national estimates. CVD was compared across groups by use of the Rao-Scott chi-square test. Multivariable logistic regression was used to estimate the likelihood of CVD in VWD patients after adjustment for age, gender, and CVD-related risk factors.

The prevalence of CVD in VWD patients was less than the prevalence of CVD in non-VWD patients (15.0% versus 26.0%). VWD was associated with a decreased likelihood of CVD after adjustment for age, gender, and CVD-related risk factors (odds ratio0.85; 95% confidence interval0.79-0.92).

These findings indicate that the risk of CVD is decreased among VWD patients, and that VWF deficiency may be protective against CVD.

These findings indicate that the risk of CVD is decreased among VWD patients, and that VWF deficiency may be protective against CVD.Given the huge dependence on dipolar, aprotic solvents such as DMF, DMSO, DMAc, and NMP in nucleophilic aromatic substitution reactions (SNAr), a simple and environmentally friendly alternative is reported. Use of a "benign-by-design" nonionic surfactant, TPGS-750-M, in water enables nitrogen, oxygen, and sulfur nucleophiles to participate in SNAr reactions. Aromatic and heteroaromatic substrates readily participate in this micellar catalysis, which takes place at or near ambient temperatures.The application of fractal geometry to describe soil structure is an increasingly useful tool for better understanding the performance of soil systems. Only a few studies, however, have focused on the structure of rhizospheric zones, where energy flow and nutrient recycling most frequently occur. We used fractal dimensions to investigate the characteristics of particle-size distribution (PSD) in the rhizospheres and bulk soils of six croplands abandoned for 1, 5, 10, 15, 20, and 30 years on the Loess Plateau of China and evaluated the changes over successional time. The PSDs of the rhizospheres and the fractal dimensions between rhizosphere soil and bulk soils during the natural succession differed significantly due to the influence of plant roots. The rhizospheres had higher sand (0.05-1.00 mm) contents, lower silt ( less then 0.002 mm) contents, and lower fractal dimensions than the bulk soils during the early and intermediate successional stages (1-15 years). The fractal dimensions of the rhizosphere soil and bulk soil ranged from 2.